Truck bolster spring



Dec. 21, 1948. c. P. LEESE TRUCK BOLSTER SPRING Filed March 4, 1944 2Sheets-Sheet l Dec. 21, 1948. I c. P.'LEESE 5 TRUCK BOLSTER SPRINGPatented Dec. 21, 1948 TRUCK BOLSTER SPRING Charles P. Lecse, Chicago,Ill., assignor to Standand Car Truck Compa poration of New JerseyChicago, III., a cor- Appllcatlon March 4, 1944, Serial No. 525,021 8Claims. (Cl. 267-9) This invention relates to truck bolster springs forrailway cars and particularly to spring assemblies including means fordamping the spring action so as to avoid excessive vibration thereof.

The principal object of this invention is to provide a friction springassembly in which shoe elements are forced into frictional engagementwith the inner perimeter of the load supporting spring by means of atension spring formed to coact with wedge faces formed on the shoes.

The invention briefly described includes a load carrying supportingspring made from material of rectangular configuration in cross section,a plurality of friction shoes positioned within the spring so as to bearagainst the inner perimeter thereof, and a shoe actuating springengaging the shoes and maintained under tension so that the resilientforce exerted by the spring will cause the shoes to press against thesaid inner perimeter of the load supporting spring.

The invention is illustrated in two specific embodiments in theaccompanying drawings, wherein:

Fig. [is a vertical section of a friction spring assembly constructed inaccordance with this invention.

Fig. 2 is a plan view of the structure shown in I Fig. 1.

Fig. 3 illustrates the construction of one of the shoe members shown inFig. 1. Fig. 4 is a view in elevation showing the shoe actuating springbefore it is installed in the assembly.

Fig. 5 is a vertical sectional view similar to Fig. 1 illustrating amodified construction.

Fig. 6 is a view in perspective of one of the shoe members employed inthe modified embodiment.

Fig. 7 illustrates the shoe actuating spring of I said modifiedembodiment; and

Figs. 8, 9 and 10 are detailed views illustrating the construction ofthe wedge members forming a part of the modified embodiment.

Referring first to the embodiment shown in Figs. 1 to 41, inclusive, ofthe drawing: I0 designates the load supporting spring, I I one of thefriction shoe members, and I2 a tension spring for holding the shoemembers in frictional engagement with the inner perimeter of the loadsupporting spring.

The load supporting spring III is preferably made from stock ofrectangular cross section so that the spring when formed will providefiat inner faces I3 of substantial area against which the outer faces ofthe shoe members I I will engage. The several friction shoe members IIare of identical construction and consist in each case of a bar, havingcurved outer faces corresponding to the curvature of the inner perimeterof the load supporting spring. The inner face of the shoe is providednear the upper and lower ends thereof with inwardly projecting portionsI4 and iii, the outer faces of which are inclined to provide wedgeforming surfaces I8 and I1. These surfaces are in the form of conesegments so that when the several shoes are arranged in their assembledrelation, as illustrated in Figs. 1 and 2, the said wedge formingsurfaces provide oppositely arranged truncated cones. The transversewidth of the shoes are normally such that when they are arranged withinthe load supporting spring I0, the edges of adjacent shoes are spacedapart, as indicated in Fig. 2 by the reference character I 8, therebypermitting the free radial movement of the shoes.

,The shoes are pressed against the inner perimeter of the loadsupporting spring by means of a shoe actuating tension spring I2, theopposite ends of which are formed with outwardly flared wedge portionsI9 and 20 which, when the spring is in its applied position, engage thewedge forming faces I6 and I! of the shoes, whereby the force exerted bythe intermediate portion of the spring I2 tends to draw the outwardlyflared wedge portions of the spring against the surfaces I6 and I l andthereby press the shoes radially outwardly against the inner faces I3 ofthe spring I0. The outwardly flared end portions of spring I2 include aplurality of the coils of the spring which are preferably formed inclose contact with. each other so as to provide relatively rigid wedgeportions for cooperation with the wedge portions of the shoes.

When assembling the several elements shown in Fig. l, the spring 92 isstretched to a greater extent than is shown in Fig. 1 and held in thiscondition by suitable means, not shown. This tensioned condition of thespring permits the shoes to be arranged about the spring I2 insumciently close relation to permit the shoes to be inserted into thecylindrical space defined byv spring Iii. After the shoes are insertedin the said spring, the tensioning device may be removed so as to permitthe outwardly flared ends of the spring I2 to fit against the wedgeforming surfaces I 6 and I I of the shoes.

The modified embodiment shown in Figs. 5 to 10, inclusive, include aload supporting spring III- which corresponds to the load supportingspring of the previous embodiment. The friction shoe except that the,ing engagement with the 1 means of a tension spring 21. The, spring ispreferably of. uniform Wedge-forming faces spring.

, tion, and arranged members are here designated by the reference iiidtwas sure on said wedge-forming faces or theshoes {to numeral 2! and-areof the same general construc--' 4.

tion as the shoes Id 45, instead of being formed with conical wedgeforming faces areformed with flatdownl wardly inclined faces 22 andmembers2l-25 are formed with surfaces 26 as shown to bear against theinclined surfaces the shoes. The wedge members 23. A-p'airof wedgediameter. throughout and is provided at opposite ends with eyelets 28-49which extend through-elongated slots'ili formed in the bottom portion ofthe wedge members. Re-

taining pins 3l-32 extend through'the eyelets of the spring and seat'inretaining grooves 33 formed in the bottom portion of said wedge membersand extend at right angles to the-slot 3 0., The spring 21 is normallyformed with its coils closed, as shown in Fig. '7'. When the spring isassembled, it is tensioned so as to spread the coils apart as indicatedin Fig. 5, whereby the force exerted by the spring tension draws thecup-shaped wedge members into wedging engagement with the inclined facesI claim: 7

. 1. A friction bolster spring for'a railwaycar truck comprising a loadsupporting helical spring.

22-23 of theshoes.

of the previous embodiment inwardly projecting, portions four converging1- best in Fig. and adapted are held-in wedgsurfaces 22-23 by Fformed'fromstock'of rectangular cross-section so, friction surfaces on 1 4 {Afriction bolster 'spring'forairailway car as to provide' relatively wides for engaging? and exerting PIES-f s m n-ou ward a n ih l dbum rims'truck comprisinga load supportinghelicalsprin its inner perimeter,-friction shoes arranged withi my sepp r in sp in tob a xa'gamst r I Ieach shoe being provided on its inner face ,with' a' p'air of inclinedsaid inner surfaces of; the spring,-

faces' in the form; of cone segments: which con- 've'r'ge towardthelong'ltudinal center ofthe load outwardly flared conical;wedgeportions for en-' 1 gaging the inclined :faces on said-"shoesformed at 'supportingspi'in'glgflshoe actuating helical spring Oppositeends withss'everalf'ioi, its con-' volutions arranged incloserelationito provide v and the intermediateportion of 'g the wedgeactuating s'pring being normally under tensionto exert pres- I sureon'the said inclined faces of said shoes. 7

' 5. A frictionjbolster spring for a railwaycar 1 load supportingspring,

a plurality of friction shoes arranged within the load supporting springand bearing directly against the inner perimeter thereof; each shoebeing provided on its which converge toward the longitudinal center ofthe load supporting spring, and a tension spring arranged within'thespace defined by said shoes and provided at opposite ends with coils ofprogressively increasing diameter to form integral wedge portions forexerting pressure on said wedge-forming faces to press the shoesoutwardly against the load supporting spring, I

I 2. A friction bolster spring for a'railwa car truck comprising a loadsupporting helical spring, a plurality of friction shoes, arcuate incross section, and arranged within the load supporting spring to beardirectly against the inner perimeter thereof; each shoe being providedon its inner face with a pair of wedge forming faces which convergetoward the longitudinal center of the load supporting spring and arepositioned in horizontal alignment with the corresponding wedge formingface of an adjacent shoe, means for forcing the shoes outwardlyincluding outwardly flared wedge portions engaging the wedge-formingfaces on said shoes, and a tension spring ar ranged within the spacedefined by said shoes and connected to said wedge portions for pressingthe shoes outwardly against the load supporting 3. A friction bolsterspring for a railway car truck comprising a load supporting. helicalspring,

being provided on its inner inner face with a pair of truck comprising aload supportinghelical spring, a plurality of-jfriction shoesarrangedwithin the load supporting'spring'to bear against the innerperimeter thereof; each shoe being provided on its innerface with apairof inwardly; projecting wedge portionshaving flat inclined faceswhich converge, toward-the longitudinal center. of the arranged to seatagainst site ends. to said' wedg'e follower members andnormallytensionedso' astoexert pressure against;

the shoesto press them outwardlyiagainst the inner perimeter of the loads'upporlting' 'spring.

6. A friction bolster'springforl a railwaycar. 5

load supporting spring, wedge follower members of cup-shapedconfiguration havingslots' formed in their bottom sides and ar'ranged'toseat against the wedge-forming faces of said shoes, and atension springformed with eyelets extending through the said'slots of the wedgefollowers, pins extending through said eyelets to connect said tensionspring with thesaid follower members' whereby the forceexerted bysaidspring is transmitted throughthe said wedge followers to the shoesso as to force'the shoes-outwardly against the load supporting spring.

face with a pair of wedge-forming faces in the form of cone segmentswhich converge toward the longitudinal center of the load supportingspring. and extension spring arranged within the space defined by saidshoes and provided at opposite ends with coils of progressivelyincreasing diameters to form outwardly flared cone-shaped members eachcorresponding -ployed and seating on the wedge-forming faces ofinterposed between and connecting said wedge members where- 7. Afriction bolster spring fora railway car truckcomprising a loadvsupporting helicalspring and means for damping the vibratory movementsof the spring comprising a plurality of shoe members arranged within thespring to bear against the inner perimeter thereof; each shoe beingformed adjacent its upper and lower ends with inwardly'projectingportions having flat inclined faces to provide wedge surfaces, a pair ofcupformed with wedge-forming faces in number to the saidshoes'emsaid'shoes, and a tension spring by the force exerted 'by thespring is transmitted through the wedge members to the-shoes to forcethem outwardly against the load supporting spring.

wedge follower members said inclined faces of j' said shoes, atensionspring connected atoppohaving-flat inclined. face which 8. Afriction bolster spring for e railway celtruck comprising a loadsupporting helical spring and means for damping the vibratory movementsof the spring comprising a plurality of shoe memhers arranged within thespring to hemagainst the inner perimeter thereof; each shoe being formedadjacent its upper and lower ends with in werdiy projecting portionshaving fist inclineci feces to provide wedge surfaces which convergetoward the center of the load supp'o spa, e

pair. of cup-members each formed with weciseforming faces correspondingin Rib 82 to the said shoes employed and seating on the wefigeferg fecesof said shoes, and a tension sprin interposed between and connectingsaid wedge members whereby the force exerted by the spring istransmitted through the wedge members to the shoes to force themoutwardly against the iced supporting spring, and the said cumshepedwefige REFERENCES (WEED The following references are of recore in thefile of this petetit:

UNITED STATES PATENTS Number Name Date 1,127,657 Mck Feb. 9, 19151,168,4i8 Westinghmise Jim. 18, 1916 1,757,437 Muidoon May 6, 19302,097,523 Hedgcock et el Nov. 2, 1937 2,182,917 Dentier Dec. 12, 19392,2i9,@iii a ir: Oct. 22, 1940 2,254,781 Rebbitt i-'. Sept. 2, wi l

